This application claims the benefit of Korean Application No. 99-27245, filed Jul. 7, 1999, in the Korean Industrial Property Office, the disclosure of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to an optical recording medium and more particularly, to a recording medium for storing attribute information on a sector, which is a basic recording unit, and a method of identifying the type of data using the attribute information.
2. Description of the Related Art
In optical discs like digital versatile disc (DVD)-type discs, a sector is the minimum division unit for data access (xe2x80x9cbasic recording unitxe2x80x9d, and at the front of each sector, there is positioned an identification data (ID) area containing all information about (attributes of) the sector. This ID area corresponds to a data identification data (DID) area in a digital versatile disc-random access memory (DVD-RAM). Specifically, identification information in the ID area, to which 4 bytes are assigned per sector, includes sector information and sector number as shown in FIG. 1. The sector information contains sector format type, tracking method, reflectivity, linking type, area type, data type, and layer number.
The detailed structure of the currently prescribed sector information area of a digital versatile disc-recordable (DVD-R) and a digital versatile disc-rewritable (DVD-RW) will be described with reference to FIG. 1. The sector format type of bit position b31 indicates whether the sector format is constant linear velocity (CLV) or zoned constant linear velocity (ZCLV) as follows:
0: CLV format type
1: Zoned format type
The tracking method of bit position b30 indicates whether the tracking method is pit tracking or groove tracking as follows:
0: Pit tracking
1: Groove tracking
The reflectivity of bit position b29 indicates whether the reflectivity is greater than, or less than or equal to 40% as follows:
0: greater than 40%
1: less than or equal to 40%
Bit position b28 is reserved.
The area type of bit positions b26 and b27 indicates whether the area is a data area, lead-in area, lead-out area, or the middle area of read-only discs as follows:
00: data area
01: lead-in area
10: lead-out area
11: middle area of read-only discs
The data type of bit position b25 denotes whether the data is read-only or linking data as follows:
0: Read-only data
1: Linking data
Finally, the layer number of bit position b24 denotes whether the layer number is of single or dual layer discs as follows:
0: Layer 0 of dual layer discs or single layer discs
1: Layer 1 of dual layer discs.
As shown in FIG. 1, among the currently prescribed sector information of a DVD-RAM, the sector format type of bit position b31, tracking method of bit position b30, reflectivity of bit position b29, reserved bit of b28, and layer number of bit position 24 are the same as the corresponding contents and bit positions defined in the DVD-R/RW. Area and data types prescribed in the DVD-RAM will follow. The area type of bit positions b27 and b26 indicates whether the area is a data area, lead-in area, lead-out area, or reserved area as given below:
00: data area
01: lead-in area
10: lead-out area
11: reserved
The data type of bit position b25 denotes whether the data is read-only or rewritable data as given below:
0: Read-only data
1: Rewritable
The structure of the ID area described above has the following problems. In the case of the DVD-RW, the basic physical format utilizes DVD-R standards, so that the data of each sector includes only read-only and linking data. DVD-RWs are remarkably different from DVD-Rs in that data can be erased and re-recorded numerous times. However, the ID area of DVD-RWs is not defined to indicate whether or not the type of data recorded in a basic recording unit is rewritable data. Therefore, there is a need for a method or area for indicating upfront that rewritable data is recorded in a sector.
Thus, a method of representing all three types of data stored on a DVD-RW(read-only, linking and rewritable) is basically required. Furthermore, a method of using another bit is also required because three types of data are not recordable with only 1 bit (See bit position b25 in FIG. 1.) under the conventional standard. However, for the sake of the consistency of ID area structures that DVD-type discs have, the data type needs to be divided into practically usable data such as read-only and rewritable data, and otherwise such as linking data.
To solve the above problems, it is an object of the present invention to provide a recording medium for storing information which indicates data type as distinguished between rewritable, read-only, or linking data on an identification data (ID) area where information relating to basic recording units is stored on a unit-by-unit basis.
It is another object to provide a recording medium for storing information about the data type, which is classified into practically-usable data such as read-only and rewritable data and non-practically-usable data such as linking data, for the consistency of ID area structures which DVD-type discs have.
It is another object to provide a recording medium on which the data type may be indicated using attribute information stored in an ID area, for the consistency of ID structures which DVD-type discs have.
It is another object to provide a method of identifying the data using information about data type which is stored in an ID area which can store all information about basic recording units on a unit-by-unit basis and is classified into practically usable data such as read-only and rewritable data and non-practically usable data such as linking data.
It is another object to provide a method of determining whether the data recorded in a basic recording unit is rewritable data, read-only data, or linking data, using attribute information stored in an ID area.
It is a further object to provide a recording medium and method by which combinations of data recorded in a basic recording unit are used to distinguish between rewritable data, read-only data, and linking data.
It is a still further object to provide a recording medium and method by which combinations of data recorded in a basic recording unit using a conventional standard are used to distinguish between rewritable data, read-only data, and linking data.
Additional objects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Accordingly, to achieve the above objects of the present invention, there is provided a recording medium for storing information relating to the attributes of a basic recording unit in a predetermined area, wherein information representing the data type of data recorded in the basic recording unit as read-only, rewritable or linking data, is stored in the predetermined area
Furthermore, there is provided a recording medium for storing a plurality of kinds of field information representing the attributes of a basic recording unit in a predetermined area, wherein the recording medium indicates whether data recorded in the basic recording unit is read-only, rewritable, or linking data by combining two or more kinds of field information selected from the attribute information.
A method of determining data recorded on a recording medium in which information in a basic recording unit is stored in a predetermined area, includes reading out information relating to data type selected from attribute information stored in the predetermined area, and determining whether data recorded in the basic recording unit is read-only, rewritable or linking data, based on the data type information.
Moreover, a method of determining data recorded on a recording medium, in which a plurality of kinds of field information denoting various attributes of a basic recording unit is stored in a predetermined area, includes combining a predetermined number of different kinds of field information, and determining whether the data recorded in a basic recording unit is read-only, rewritable, or linking data, based on the combined field information.